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Sawdust Maker
25th November 2010, 07:57 PM
I bought the 5/8 U for roughing down
Have to admit I wasn't impressed when I used it. no cutting action on the tip. Had a closer look, hadn't quite ground it down enough :doh: (And no I haven't handled it yet)
Just goes to show, must wear glasses (god I hate the declining eyesight of middle age) :C

rsser
25th November 2010, 09:34 PM
Nick, you can look forward to adding some hearing loss to the mix too.

John, will do.

rsser
28th December 2010, 02:03 PM
Just one comment about Doug's fine tools, which may or may not apply depending on the heat treatment process.

has warned that the tip of HSS tools can be weak as a side effect of that process so don't judge the edge quality until you've ground a few mm back.

I say this cos I was experimenting with honing out the milling marks on the shallow detail gouge using the Tormek profiled wheel and their 'toothpaste' ;-}

I rolled off the leather, the tip hit the plastic and chipped out.

No drama, cos it was destined to be reground using std Tormek settings.

Best match I could achieve was 75mm projection, hole A on the TTS, and JS 1.

Off the coarse graded Tormek, I then worked at honing the bevel with the toothpaste and found it didn't do much on Doug's high vanadium steel (and I'm repeating this cos I see Doug is logged on ATM.).

Doug Thompson
28th December 2010, 04:35 PM
Erm,
Personally without any fact to back it up it does seam like tools work better when they have been ground a couple times... it could be as simple as the grind changes so they feel better but I don't know. The edge chipping normally doesn't happen even when steel hits against steel. This steel has a complete heat treatment from the hardening to tempering and the cryogenics more than any other steel on the market today but I think there is a way to make it better... time will tell.

rsser
28th December 2010, 05:54 PM
Doug, please don't take my post as a criticism. It's not.

is a production turner who goes through HSS tools at a rate of knots, so his experience counts for something. His favoured steel is Henry Taylor which is far from rubbish.

FWIW, when I first installed and used a Hock A2 Cryo blade in a Stanley handplane I got a chip in the edge, and I wasn't being ham fisted.

Doug Thompson
29th December 2010, 03:20 AM
Ern,
I do understand and thought nothing wrong... at times I just don't have a answer why something happened.

What I do know is I found someone who can push this steel a bit farther so testing is being done right now to see how far it can go.

Sawdust Maker
29th December 2010, 08:26 AM
Nick, you can look forward to adding some hearing loss to the mix too.

John, will do.

eh? what's that you say?
I'll be ordering one of these soon, probably the only thing covered by health insurance

157002

rsser
29th December 2010, 08:31 AM
Cool.

Whack a stocking-ette over the funnel to keep the chips out ;-}

rsser
9th January 2011, 04:43 PM
Just to add a comment or two, as there's been posts elsewhere as well ...

The 5/8" U gouge is a tool I'm still coming to grips with.

The closest Tormek settings I could get are JS4, 65mm projection and A hole on the TTS. But you need to emphasise tip grinding to avoid a concave wing.

The 1/2" shallow detail gouge is a gem; prob the closest to a long and strong that's come out of the new world but others are more qualified than me to judge that.

Tormek settings for that: JS1, 75mm projection, A hole on the TTS.

Thanks again to Neil, Nick and Doug T.

Sawdust Maker
9th January 2011, 07:54 PM
Ern

can you post a piccy of the end of the 5/8 showing the grind please

rsser
10th January 2011, 11:25 AM
Here you are Nick.

And a front view of the orig. grind can be found here (http://www.woodworkforums.com/f8/thompson-5-8-u-gouge-first-impressions-129319/)

Doug Thompson
10th January 2011, 04:30 PM
Ern,
Here's another thread about grinding... I don't have time to copy and paste this over here but you can.
Bowl gouge basic grind profile (http://www.sawmillcreek.org/showthread.php?156654-Bowl-gouge-basic-grind-profile)

rsser
10th January 2011, 04:35 PM
Thanks Doug.

NeilS
11th January 2011, 11:29 AM
I have found this maxim very helpful since I first heard it from Doug.


Notice the basic shape of the flute is carried over to the grind, if you look down the flute and straight down on the grind the shape won't be perfect but very close. The wings will be ground to this profile and the gouge will work like a charm, small changes like grinding the wings back won't affect the tool much at all but major changes the tool won't cut. This basic idea can be used on any bowl gouge....Here are photos by Doug of his two flute types that show the pilot grind to establish the profiles.

158354
158355

And here he has completed the bevels on one side.

158374

And here the bevels on both sides.

158361

And to illustrate further, here are some pics of two of my gouges, first pair is a Thompson 'V' and the second a P&N 'U' flute.

158356.....158357


158358.....158359

I use slightly longer wings on the U flute than specified, but the bulk of the tip meets the maxim.
.

Sawdust Maker
11th January 2011, 12:10 PM
Ern

Thanks for the piccy

Neil

Thanks as well

Here's mine as used on the weekend to rough shape some silky
I need to take a little more off the wing towards to top.

158362

My Tormek settings were/are: JS 2, 65mm projection, "A" hole on the TTS

I've also attached Ern's piccy again for easier comparison

158363

rsser
11th January 2011, 04:02 PM
Good info Neil. Thanks for taking the trouble.

Nick, with what you've got I'd be inclined actually to spend more time grinding at the tip to get a convex wing, but my weakness is not being able to imagine variation in three dimensions so perhaps could step in and advise, or start another thread. Maybe repeating for the memory-challenged among us the relationship in the T gouge jig between JS, projection and mount bar distance in terms of wing outcomes.

RETIRED
11th January 2011, 04:44 PM
Will answer later tonight.

hughie
11th January 2011, 08:48 PM
What I do know is I found someone who can push this steel a bit farther so testing is being done right now to see how far it can go

Doug,harkening back to my toolmaking days many years ago.

The process is/was based around a couple of basic points
[a] accurate temperature measurement and the knowledge that all heating ovens aint equeal :U
[b] Knowledge of the steel being worked, something akin to the art of the master coffee roaster.A black art of sorts, learnt by experience and pushing the limits.

If you can find the right guy, he might amaze you. I have seen toolmakers with 40-50 years under their belts produce some amazing results.

Look forward to what turns up :2tsup:

Doug Thompson
12th January 2011, 04:18 PM
Neil,
Thanks for posting this info. One thing that can be shown from these pictures is the U shape gouge is not the best choice for roughing because of the large nose radius and small wings... this works well in a push cut. The V shape has large wings that are needed for roughing, the wing shears the wood and the force is directed into the tool rest. Pick a flute shape for the cut you want to make.

The grind is simple if break it down.

First get the nose angle roughed to the basic angle - 40 degrees for spindles and 60 degrees for bowl gouges.

Second rough the basic arch that will be the cutting edge of the wings.

Third grind the wings to meet the top of the arc.

Grinding is very easy if you keep it simple, simple grinds work just as well as complex grinds.



I have found this maxim very helpful since I first heard it from Doug.

Here are photos by Doug of his two flute types that show the pilot grind to establish the profiles.

158354
158355

And here he has completed the bevels on one side.

158374

And here the bevels on both sides.

158361

And to illustrate further, here are some pics of two of my gouges, first pair is a Thompson 'V' and the second a P&N 'U' flute.

158356.....158357


158358.....158359

I use slightly longer wings on the U flute than specified, but the bulk of the tip meets the maxim.
.

Jim Carroll
12th January 2011, 05:50 PM
Neil,
Thanks for posting this info. One thing that can be shown from these pictures is the U shape gouge is not the best choice for roughing because of the large nose radius and small wings... this works well in a push cut. The V shape has large wings that are needed for roughing, the wing shears the wood and the force is directed into the tool rest. Pick a flute shape for the cut you want to make.

The grind is simple if break it down.

First get the nose angle roughed to the basic angle - 40 degrees for spindles and 60 degrees for bowl gouges.

Second rough the basic arch that will be the cutting edge of the wings.

Third grind the wings to meet the top of the arc.

Grinding is very easy if you keep it simple, simple grinds work just as well as complex grinds.

Doug it seems like it is time to do a short video for U tube showing how you grind the tools.
Just need to get a camera that allows you to get in close and personal and show clearly what you are doing.
Some try to do it standing about 4 feet away and makes it hard to get a clear picture of what is going on.

Sawdust Maker
12th January 2011, 06:56 PM
Neil,
Thanks for posting this info. One thing that can be shown from these pictures is the U shape gouge is not the best choice for roughing because of the large nose radius and small wings... this works well in a push cut. The V shape has large wings that are needed for roughing, the wing shears the wood and the force is directed into the tool rest. Pick a flute shape for the cut you want to make.

....

Looks like I should have ordered the v shaped gouge, as the initial roughing was my intended use :doh:
OK, when's the next order? :U

NeilS
12th January 2011, 10:40 PM
OK, when's the next order? :U

My hands are firmly in my pockets...:rolleyes:
.

Sawdust Maker
13th January 2011, 10:15 AM
My hands are firmly in my pockets...:rolleyes:
.

Don't worry
I'll need a little time to save up for such a (non) essential purchase

Ross
13th January 2011, 12:21 PM
Nick

Would you like to try mine?

Ross

Sawdust Maker
13th January 2011, 01:54 PM
Nick

Would you like to try mine?

Ross

Ross
Thanks for the offer
Would love to :2tsup:
After the boys go back to school in about 3 weeks would be good

rsser
30th January 2011, 02:08 PM
As posted elsewhere Nick, it works as a roughing gouge though takes a bit more pounding than the V.

I start by knocking the corners off my octagonal blanks and then come in with a push cut from the headstock side with enough bite for the bevel to rub on much of the circumference. If there's too much bouncing around you can backtrack and take more off the corners, or speed up the lathe, or increase the pressure of the hand on the shaft down on the rest and slow the rate of push.

...

In terms of bevel geometry a reread of the Tormek manual (yeah, against The Code) indicates that when bevel angle and projection through the jig are held constant, each higher number on the Jig Setting produces more swept back wings.

Bitshird
31st January 2011, 11:32 AM
My son in law got one of Doug Thompson's outstanding tools this past Friday, we were exhibiting at the same show in Nashville Tennessee, "The Home Of Country Music" I have a couple of Dougs older tools about 2 years old. Being a Machinist and tool maker I have to tell you the new heat treating facility that Doug is using now is great, the tools appear to a better finish as well, and Andrew's cut great right out of the package, it's one of Doug's 1/2 inch V Bowl Gouge's the angle and wings were pretty well spot on.:2tsup: